Just a little rundown here. Ive got a 1951 body and frame and a 1960 235. I’m converting it to 12v. Ive added a new coil, an alternator, new battery. I’m just trying to get it started. Below are photos wit questions. Please comment and advise as needed
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
You need to wire up the coil properly using the ignition resister. There is a good write up in today’s news. Ignition wire(hot) needs to go to resistor, then to coil. Wire from side terminal at starter to coil also. This wire provides 12v to coil upon starting only, then reverts to 8 or 9 volts being fed from resistor for continuous duty. Make sure you understand this operation.
A one wire alternator does away with the voltage regulator.
You can also add relays to reduce load, thus brighter headlights, etc. for large loads.
6 volt vehicles have heavier wire than required for 12 volt systems, thus that is a bonus when changing to 12 volts.
Read today’s comments, all spelled out there.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
Can you take a picture of the passenger side of the engine so we can see your wiring. That should tie your photos together so we have a better idea where the wiring goes. Also a photo of the back of the alternator where the wiring is.
Last edited by Phak1; 03/11/20211:07 PM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Would someone be able to mark this up to help me? Ive put a fair amount of time into find exactly what i need and can’t seem to find it. Or i just don’t understand.
1. Wire from ignition "ON" terminal to ballast, other side of ballast to coil pos. 2. Wire from starter solenoid "R" terminal to coil pos. 3. Wire from starter battery stud to ammeter. Other side of ammeter to ignition switch battery terminal. (provided ammeter can handle 12V system) 4. White wire (terminal 1 on 10si alternator) goes to a gen light, out gen light to Ignition "ON". or from term 1 straight to ignition "ON". Some folks use a diode inline from term 1 to ignition ON. A diode allows current to travel in one direction only. I use a light bulb, and no diode. The bulb supplies the necessary resistance for the exciter/white wire. It supplies a quick warning of low charge condition. 5. Wire from ignition switch battery terminal or from ammeter hot terminal to push button, out the push button to starter solenoid "S" terminal. 6. Yes, coil neg to dizzy. 7. Start motor.
Using an ammeter is not recommended by me, and I do not offer instructions for it. No. 3 is what the 1951 6V diagram shows.
The junction strip, if that is what it is, is not needed. Take it off.
If you have Pertronix, you didn't say. Do I see a Flame Thrower coil?
Judging by the amount of wiring I see, it might be a better option to buy a new wiring harness and go from there. They make them for 12v conversions with an alternator and contain a detailed instructions on how to wire.
FYI, your alternator is a 10SI 3 wire alternator. The big lug on the back is counted as as one wire and the DA connector contains two wires for a total of three.
I agree with bartamos, you don’t need that terminal block mounted on the drivers side firewall. Remove it and the wire that goes to the starter.
Last edited by Phak1; 03/12/20212:46 AM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Thank you Bartamos. That’s exactly what I needed. And no I did t go with an HEI. I took you guys advice. Staying with points. I’ll get this baby wired up and see what she does.
Ok Bartamos....From your last post the attached photo is exactly how i wired it. She still didn’t start. Could you look at my diagram and see if I wired it correctly?
"5. Wire from ignition switch battery terminal or from ammeter hot terminal to push button, out the push button to starter solenoid "S" terminal."
"5. Wire from battery side of ammeter to push button, out push button to starter solenoid "S" terminal." This may not make any difference, since I assume the motor is cranking but not starting. Make this change anyway. I assume it is cranking but not firing at all, correct?
If no start: With key on, Check for 12V at coil pos.... and for 12V at Ign Sw ON terminal. Don't do anything else. Report.
Of course I have to say this in order to be careful...... Except for my mis leading wording, which you will correct, the drawing matches my instruction. I do not know if you have wired it according to your drawing.
Only other thing is: "3. Wire from starter battery stud to ammeter. Other side of ammeter to ignition switch battery terminal. (provided ammeter can handle 12V system) " What you show is the same electrically but not per the original wiring diagram or my no. 3 in red.
The cable from battery positive post to starter stud is a given. That is correct on your drawing.
One thing I don’t see in your diagram (or in your instructions bartamos), is it doesn’t have any wire from the alternator to charge the battery. To be clear, the stud at the back of the alternator that presently has the red wire going to the DA plug, also needs a second 10 gauge wire going to somepart of the positive side circuit of the battery to enable charging.
I’m sure it was just an oversight. Bartamos, can you elaborate?
Last edited by Phak1; 03/26/20212:20 AM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Trying to stick to ignition for now. Starting the motor needs no charge circuit. He asked about the white wire so I veered off course to answer that in my instruction list. I also said "Using an ammeter is not recommended by me, and I do not offer instructions for it. No. 3 is what the 1951 6V diagram shows."
A three wire hook up is, as you know, Battery positive post, or starter stud, to alternator battery stud. Alternator blade terminal 1 goes goes to ign thru a bulb (idiot light). Alternator blade terminal 2 goes to alternator battery stud.
"4. White wire (terminal 1 on 10si alternator) goes to a gen light, out gen light to Ignition "ON". or from term 1 straight to ignition "ON". Some folks use a diode inline from term 1 to ignition ON. A diode allows current to travel in one direction only. I use a light bulb, and no diode. The bulb supplies the necessary resistance for the exciter/white wire. It supplies a quick warning of low charge condition."
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Back of ammeter shows 12v so I’m assuming it can handle this. And yes it’s turning over but not firing. Does the vacuum advance need to be hooked up to start?
Does the vacuum advance need to be hooked up to start?
No, but the vacuum port on the carburetor needs to be plugged or you’ll have an open vacuum leak and it won’t idle.that’s just to start. It does need the advance to run right.
It may be easier to just hook it up.
Last edited by Phak1; 03/26/20219:07 PM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
No. but looks like you may have wired it correctly only to discover you have some other issue. Plug open ports as said. 1. Check for 12V at coil pos with key on. Not cranking. 2. If 12V at coil, CHECK POINTS GAP. then take out a spark plug, keep wire attached, place threads only of spark plug on good bare metal ground. Key on, crank motor 5 sec minimum, watch for spark. Report
Does your coil say "Internally resisted" or "Externally resisted"?????????
Do you see gas squirting down carb when throttle is operated or did you try squirting some in there?
Trying to take this slow and careful rather than jumping all over the place with the 40 things that could be wrong. One of THE most important things to start with in your case is history. 1. When is the last time you heard it run? 2. Has anyone taken out the distributor? or done work on it? 3. Has anyone done any work on the carb? 4. If yes to 2 or 3, was that before or after last time you heard it run?
It does not matter which you choose for battery hot and which for ignition "ON", just so you know which is which and they are separate terminals. They are either all connected to each other or all disconnected to each other when switch is operated. So mark the switch yourself. When wired, you will find that one is always hot no matter the key position and the other two will only be hot with key on. So those two become "ignition on/run" terminals. Kapish?
It will show the correct amps flowing through it The voltage at which those amps are delivered will affect the total power Which will now be twice as much per amp delivered But the amp meter is not a power meter
1 amp is 1 amp No matter the voltage, 1 volt or 6 or even 12 volts The power will be different however Because the voltage drop that the amp “falls” through does work Like dropping a bowling ball on your foot from you hand or off the roof Same bowling ball, but falling from the roof top sure as heck would do more work on your foot -s
The ammeter is not an issue. No reason to dwell on it at this time. Waiting for voltage tests to get motor started. If we think it has anything to do with the ammeter, we will take it out of the circuit. You may be confusing the poster into thinking that we care about if the ammeter can handle the voltage/amperage/bowling balls. Lets have this discussion after we get the motor running.
When I said "provided ammeter can handle 12V system" I should have said "provided the ammeter can handle the alternator amperage and any added loads." The voltage won't matter but the old ammeter shunt design/resistance may not protect the ammeter coil wires. Don't know. If the alternator supplies higher amps to a higher load demand, it could burn out the ammeter. But that still won't affect the circuit or starting.
OK i got an update. Below is exactly how i have it wired. The odd thing about this configuration is no matter what position the key is in the motor will turn over. When i turn the key to on the ammeter measures 12v. The coil (Flame Thrower) measures 45v. I don’t not have alternator wired at all. I just drew it on here for my information. Also I do not have the AUX wire from POs battery term connected to anything.
Bartamos remember when you chewed my [censored] out for removing distributor? I found TDC when putting it back in so i believe its in correctly.
The odd thing about this configuration is no matter what position the key is in the motor will turn over.
The reason the starter operates without the key, is it doesn’t go thru the ignition. Its wired directly from the battery. The engine won’t without the key in the on position.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
You mistested the coil test. Set multimeter to DC volts, low range. Red probe of meter on coil positive, black probe of meter to good bare metal ground. Turn key on and off and see what the voltage reads. It ain't 45V. This test is without motor cranking.
And THEN..........measure coil positive with key ON, while cranking. By the way, there are two Top Dead Centers for each cylinder. One is the right place, one is the wrong place.
Commentary: I know that checking a spark plug for spark is faster and easier and bypasses all these little voltage tests. But a meter is more reliable from posters. Sometimes it's not the way I would do something but what suits other levels of experience.